SetString(const char *, const char *, size_t) method

value
The string value. Passing NULL is equivalent to calling the SetNull method.

len
Optional. The length of the string in bytes or the UL_NULL_TERMINATED_STRING constant if the string
is null-terminated. The SQLE_INVALID_PARAMETER constant is set if the len value is set larger than 32K. For large strings,
call the AppendStringChunk method instead.